A processing apparatus for fluid with a simple structure, high productivity, ability of precise dispersion, emulsification and grinding, is provided.The apparatus of the present invention comprises at least two processing faces of a first face and a second face, both of which are arranged in a tight-closed passage, and positioned opposite to each other to constitute part of said passage, and a contact pressure applying mechanism for putting both faces 1, 2 into closed contact with each other, wherein the rotation of the second processing face 2 in respect of the first processing face 1 may cause dispersion or emulsification of the fluid to be processed between both processing faces 1, 2. The first and second processing faces 1, 2 are placed in closed contact with or adjacent to each other by means of said contact pressure applying mechanism, and the fluid to be processed is actuated by said rotation to pass between the first and second processing faces 1, 2, as it is forming fluid films between said processing faces 1, 2, so that said fluid will be emulsified or dispersed to a desired extent.